1. Field of the Invention
The present invention relates to a ground joint connector, and in particular, relates to reduction of the number of components regarding the ground joint connector, and reduction of the number of ground holes provided in an automobile body, so as to make assembly and mounting of ground portions of a wire harness simpler and easier.
2. Description of Related Art
To establish a ground connection of electric wires forming wire harnesses mounted on an automobile, an end of each electric wire is connected to a terminal, and the terminal engages with a joint connector. Thus, the wire harness is grounded to an automobile body, and so on, via the joint connector.
As shown in FIG. 4(A), in a conventional ground joint connector, male tab portions 7a formed at the end of a joint bus bar 7a are respectively inserted into and engage with terminal holding portion 8b in a housing 8a of a female connector 8. As shown in FIG. 4(B), a terminal 6 connected to an end of an electric wire w is inserted into and engages with a connector housing 5a of a male connector 5. Then, the male connector 5 engages with the female connector 8, in order to connect each terminal 6 to the joint bus bar 7. The joint bus bar 7 is provided with a ground terminal 7b. 
FIG. 5 illustrates a wire harness w that is grounded to an automobile body using the joint connector. The joint connector, which includes the male and female connectors 5 and 8 to engage with one another, is mounted on an automobile body panel P. A ground terminal 7b projecting from the joint bus bar 7 is aligned with a ground hole Pa provided in the automobile body panel P. Then, a bolt B is inserted into the aligned ground terminal 7b and the ground hole Pa, and is threaded into a nut N fixed on a rear surface of the automobile panel P. Thus, a ground connection to an automobile body can be provided.
According to the conventional ground joint connector described above, the female connector 8, as shown in FIG. 4(A), is formed by inserting each male tab portion 7a of the joint bus bar 7 into each terminal holding portion 8b of the housing 8a, so as to engage with one another. On the other hand, at the wire harness W/H side, as shown in FIG. 4(B), a (female) terminal 6 press-fit to an end of each electric wire d forming the wire harness W/H, is inserted into each terminal holding portion 5b of the housing 5a of the male connector 5, so as to engage with one another.
Since the ground connection of the wire harness W/H is provided as described above, many components, such as the housing 5a of the male connector 5, the female terminals 6, the housing 8a of the female connector 8, and the joint bus bar 7, are required. Thus, the requirement of many components results in a high cost. Further, since many components are required, assembly of each component and assembly (connection) among the components require more load and time. Thus, the assembly of the wire harness is prevented from being efficient.
Further, since, in the ground joint connector described above, the ground terminal side connector (female connector 8) and the wire harness side connector (male connector 5) are connected one-to-one, when many wire harness side connectors are required to ground wire harnesses, ground terminal side connectors respectively corresponding to the wire harness side connectors are also required. In addition, since ground terminals for the respective joint connectors should be connected to the automobile body panel, the number of ground holes provided in the automobile body panel also increases.
Accordingly, the present invention is provided in view of the above-described problems, and an objective of the present invention is to reduce the number of components regarding a ground joint connector, to use common components, and to miniaturize the components. At the same time, another objective of the present invention is to reduce the number of ground holes provided in the automobile body, and to make assembly and connection work regarding the ground connection efficient.
To achieve the above and/or other goals, the present invention provides a ground joint connector including at least one connector housing, each configured to receive and hold at least one terminal of at least one electric wire, and a holder that is formed from a high-conductivity resin and has a plurality of connector holding portions. Each of the plurality of connector holding portions is configured to receive and hold each of the at least one connector housing. The ground joint connector further includes a ground terminal provided on an outer surface of the holder. Each terminal of each electric wire received and held by each connector housing contacts the holder so as to be grounded via the holder and the ground terminal.
Preferably, the at least one connector housing is formed from a high-conductivity resin, and the ground terminal is formed unitarily and in one piece with the holder.
According to the ground joint connector of the present invention, the holder, configured as a female connector, and the connector housing, configured as a male connector, both of which directly hold strands (conductor) of each electric wire forming a wire harness, are made from a high-conductivity resin. The high-conductivity resin is a high conductivity electrical conductor, and according to the construction in which the electric wire is directly held between the high electric conductors, a conventional terminal, which is connected to an end of an electric wire, and a bus bar are not necessary. Therefore, the ground connection can be provided without these conventional components, and thus, the number of components can be reduced.
According to another aspect of the present invention, a ground joint connector is provided including a plurality of connector housings, each configured to receive and hold at least one terminal of at least one electric wire, a primary holder formed from a high-conductivity resin, and at least one subordinate holder formed from a high-conductivity resin. The primary holder includes a connector holding portion configured to receive and hold one of the plurality of connector housings, a ground terminal provided on an outer surface of the primary holder, and a first engaging portion provided on an outer surface of the primary holder. Each of the at least one subordinate holder includes a connector holding portion configured to receive and hold another of the plurality of connector housings, a second engaging portion having a shape substantially the same as that of the first engaging portion, and a third engaging portion configured to engage with one of the first engaging portion of the primary holder and the second engaging portion provided on an adjacent subordinate holder. The primary holder and at least one subordinate holder are electrically connected to one another by engagement of the first, second and third engaging portions. Each terminal of each electric wire received and held by each connector housing contacts one of the primary holder or the at least one subordinate holder so as to be grounded via the connector holding portion of the primary holder and the ground terminal.
Preferably, the plurality of connector housings is formed from a high-conductivity resin, and the ground terminal is formed unitarily and in one piece with the primary holder.
According to the construction described above, since plural high-conductivity resin connector housings, each of which receives and holds at least one terminal of at least one electric wire, are inserted into and engage with high-conductivity resin holders arranged in parallel, and each of which having a connector holding portion, the ground terminal can be shared because of the function of the high-conductivity resin. Thus, a single ground terminal is necessary only on a single holder. Accordingly, the holder that does not have the ground terminal can be miniaturized, and only a single ground hole is sufficient to be provided in the automobile body panel. The use of a common ground terminal and the miniaturization of the holder results in a reduction of cost of the components, and the reduction in the number of ground holes reduces time and cost, and thus improves work efficiency.
It is preferable that the holder is a female connector and the connector housing is a male connector. Further, a plurality of electric wire guide grooves are provided on a upper surface of the connector housing, and electric wires are inserted into and engage with the plurality of electric wire guide grooves, respectively. Each electric wire with exposed strands (conductor) at an end is pressed and held between the inner surface of the holder and an end face of the connector housing, when the connector housing engages with and is locked in the holder.